This invention relates generally to the preparation of structures for use in semiconductor and/or optical wave guide applications and relates, more particularly, to the growth of an epitaxial film upon surfaces, such as an alkaline earth oxide surface.
Oxides in a class of oxides known as perovskites and spinels are known to exhibit technologically-significant properties, such as ferroelectricity, ferromagnetism, piezoelectricity, superconductivity and nonlinear electro-optic behavior, and for this reason, are grown upon substrates for the purpose of incorporating these properties within electronic devices. With such oxides grown upon substrates, the aforementioned properties can be taken advantage of in a number of devices, and in particular, are believed to be well-suited for use in Faraday Rotators for optical isolators and in magnetic memory applications.
Of these electronic devices, optical guided wave (OGW) devices constructed with perovskites are relatively demanding from the standpoint of optical clarity and necessarily require long range structural coherence. Heretofore, the optical clarity and structural coherence of a perovskite film grown upon an alkaline earth oxide, such as MgO, has been limited due, at least in part, to the inability to grow a perovskite upon the alkaline earth wherein the grown perovskite is of a single orientation. It would be desirable to provide a process for growing perovskite of single-orientation upon an alkaline earth oxide and thus enhance the quality of the resulting structure for OGW applications.
Accordingly, an object of the present invention is to provide a new and improved process for growing a perovskite or a spinel of single orientation on an alkaline earth oxide and structures formed with the process.
Another object of the present invention is to provide such a process which is well-suited for coating an alkaline earth oxide surface with a single layer of a Group IVA element oxide, i.e. TiO.sub.2, ZrO.sub.2 or HfO.sub.2.
Still another object of the present invention is to provide such a structure which is well-suited for use in an OGW applications or for incorporation within an integrated circuit.
Yet another object is to provide a new and improved process for growing a perovskite or a spinel or constituents of a perovskite or spinel epitaxially upon a surface provided by a Group IVA element oxide or an oxide constituent of a perovskite or a spinel and structures formed with the process.
A further object of the present invention is to provide such a structure whose ferromagnetic properties render it well-suited for use in magneto-optic applications.